Patent EA-003240-B1 (EA)
Title: Method for annular sealing, a borehole and a tubular
Inventor: BOSMA MARTIN GERALD RENE
IPC: E21B33/14
Filed: 2000-04-05
Abstract: 1. Method for sealing an annulus between two solid tubulars or between a solid tubular and a borehole which comprises placing a thermoset or thermoplastic material between at least part of an outer surface of an expandable inner tubular and at least part of an inner surface of an outer tubular or the wellbore; and forming a seal by expanding the inner tubular, wherein the inner tubular, prior to its expansion, is substantially round in cross-section. 2. Method according to claim 1, wherein said expandable tubular is at least partly cladded with an elastomer, in which the seal is formed by bringing said expandable tubular into a borehole followed by expansion of the tubular. 3. Method according to claim 1, wherein one said expandable tubular is at least partly cladded with an elastomer, in which the seal is formed by bringing said expandable tubular into another tubular followed by expansion of said expandable tubular. 4. Method according to claim 2 or 3, wherein said thermoset or thermoplastic material is an elastomer containing a closed cell structure. 5. Method according to any of claims 2 to 4, wherein said thermoset or thermoplastic material is an elastomer also containing expanded, malleable microbubbles. 6. Method according to claim 1, wherein said expandable tubular is at least partly cladded with a thermoplastic elastomer, in which the seal is formed by bringing said expandable tubular into the borehole or into another tubular followed by expansion of the expandable tubular. 7. Method according to claim 6, wherein at least part of the wellbore or the other tubular is heated before and/or during expansion of the tubular. 8. Method according to claim 7, wherein heating is provided by means of a hot liquid, a chemical reaction or by electricity. 9. Method according to any of claims 6 to 8, wherein said thermoset or thermoplastic material is an elastomer also containing expanded, malleable microbubbles. 10. Method according to claim 1, wherein the seal is provided by placing an in-situ vulcanising elastomer into the wellbore or into another tubular, followed by expanding the expandable tubular. 11. Method according to claim 10, wherein a two component room temperature vulcanisable elastomer is used to provide the seal. 12. Method according to claim 10 or 11, wherein setting of the elastomer is carried out prior to the tubular expansion. 13. Method according to claim 10 or 11, wherein setting of the elastomer is completed after the tubular expansion. 14. Method according to any of claims 10 to 13, wherein use is made of a room temperature vulcanisable silicone rubber. 15. Method according to any of claims 10 to 14, wherein said thermoset or thermoplastic material is an elastomer also containing a chemical blowing agent and/or expanded malleable microbubbles. 16. Method according to any of the preceding claims, wherein tubulars are reeled tubulars. 17. Method according to claim 16, wherein a tubular is reeled tubular at least partially coated with an elastomer. 18. Method according to claim 17, wherein electrical cables and/or hydraulic lines are present in the elastomeric coating. 19. Method according to any of the preceding claims, wherein at least a section of the expandable tubular is surrounded by a sleeve comprising a thermoplastic or thermoset material in which a number of burstable containers are embedded, which containers comprise a chemical activator which is released into the annular space surrounding the expanded tubular and which activator reacts with a cement or other chemical composition and/or the sleeve such that said chemical composition and/or the sleeve solidifies in response to the tubular expansion. 20. Method according to claim 19, wherein the inner tubular is expanded by use of a mandrel having a frusto-conical, parabolic or elliptical shape. 21. Method according to any of claims 19 or 20, wherein said mandrel is heated. 22. Method according to any of the preceding claims, wherein the seal is provided between tubulars or between a tubular and a borehole when the deviation from the tolerance of the tubular as set by the manufacturer is at least 50% of the tolerance set. 23. Method according to claim 22, wherein the deviation of the tolerance is at least 200% of the tolerance set. 24. Method according to claim 23, wherein the deviation of the tolerance is at least 1000% of the tolerance set. 25. A well provided with a tubular sealed according to any of the preceding claims, wherein the tubular serves as a production tubular through which hydrocarbon fluid is transported to the surface and through which optionally a service and/or kill line passes over at least a substantial part of the length of the tubular, through which line fluid can be pumped towards the bottom of the borehole while hydrocarbon fluid is produced via the surrounding production tubular. 26. A tubular provided with an inner tubular sealed to said outer tubular according to any of claims 1 to 24, wherein the inner tubular serves as a transportation means for transportable fluids.